This application relates generally to dielectric waveguides. More specifically, this application relates to the formation of monolithic waveguide arrays.
Endoscopes are devices that are used to deliver images from constricted locations and/or through small openings. While endoscopes have the potential to find a wide range of application, they are currently used primarily for diagnostic medical applications. In such applications, an endoscope is inserted into a portion of a patient's body and used to collect images of the portion that may be studied by qualified technicians and/or physicians to aid in the diagnosis of disease or disorders. Medical endoscopes also find utility during therapeutic procedures, where they may be used to provide a physician with an image to aid in the performance of such procedures as surgeries and the like.
Current endoscope structures make use of such technologies as rigid gradient-index (“GRIN”) lens rods, flexible fiber bundles, and rigid relay lens systems. Of these, fiber bundle systems are the most widely used because they tend to provide somewhat better flexibility than the other structures. But, even so, such fiber-bundle endoscope structures still suffer from significant limitations in flexibility. This is a consequence of the fact that as the fiber count is increased, the diameter of the fiber bundle increases, becoming progressively more stiff. In addition, the fibers within the bundles cannot typically be stacked regularly, prohibiting the bundles from being identically matched to a grid of pixels on a camera or display chip. Another concern with fiber-bundle structures is that fibers often break, leaving dark pixels in the bundle.
Fiber endoscopes thus provide relatively low performance characteristics, are stiff and heavy, and are costly. The fact that current use of endoscopes is largely limited to medical applications is a reflection of the fact that this is one of the few areas in which these limitations are offset by the significant advantage of being able to perform minimally invasive imaging as used both diagnostically and therapeutically. But even in such medical applications, recent studies have identified risks of transferring infections among patients as endoscopes are reused because of the formation of antibiotic-resistant bacterial biofilms. There are a wide range of other applications in which endoscopes could find utility if improvements could be made in their overall performance, weight, flexibility, and cost.
There is accordingly a general need in the art for improved endoscopes and for improved methods of fabricating waveguides used in such endoscopes.